Reversible cyclic power transmission mechanism



REVERSIBLE CYCLIC POWER TRANSMISSION MECHANISM Original Filed gsept. 6,1938 3 Sheets-Sheet l L I 1 L (J ooooooooc@@@ @oo@ INVENTOR HAROLDTAVEPY 1 22 ATTON3S H. T" AVERY REVERSIBLE CYCLIC POWER TRANSMISSIONMECHANISM Original Filed Sept. 6, 1938 3 Sheets-Sheet 2 ATTO EYS ,914%.: H. T. AVERY REVERSIBLE CYCLIC POWER TRANSMISSION MECHANISMOriginal Filed Sept. s, 1938 s Sheets-Sham 3 INVENTOR i-mkmo Z'Avrw M W7%, ATT NEYa of a complete "Marchant Patented Apr. 13, 1948 REVERSIBLECYCLIC POWER TRAN S- MISSION MECHANISM Harold r. Avery, Oakland, Calif.,aasignor to Mar-chant Calculating corporation of Californi MachineCompany, a :1.

Original application September 6, 1938, Serial No. 228,613. Dividedandthis application September 18, 1944,

14 Claims.

The present invention relates to calculating machines and the likehaving cyclically and reversibly operable devices driven through acyclic power transmission mechanism and has particular reference tomeans for controlling planetary gearing or the like to cause it tooperate cyclically in either a forward or reverse diection.

Planetary gearing and similar gearing arrangements operating on the sameprinciples are susceptible of employment both as forward drivingmechanisms and as reversing mechanisms, and constitute exceedinglycompact arrangements for performing these multiple functions. However,in environments in which the gearing employed must be cyclic in itsaction to arrest the driven element always at the same rotationalposition, it has heretofore been necessary when using planetary gearingmechanism to provide for extracyclic movement of the driven element inorder to disconnect, and then to return the driven element backward toits full cycle position.

The principal object of the present invention is to make possible theemployment of such an inherently non-cyclic gearing arrangement as aconnecting means or as both a forward driving and reversing means in anyenvironment in which cyclically operating reversible power transmissionmechanism is to be employed, without requiring extracyclic movement ofthe driven mechanism for controlling or adjusting the for ward drivingand reversing means.

As an illustration of oneapplication of the invention, a powertransmission embodying the same is disclosed in connection with acarriage shifting mechanism for a Merchant calculat ing machine of thetype disclosed in the Avery patent application Serial Number 702,949,filed December 18, 1933, and since matured into Patent Number 2,211,736,issued on August 13, 1940, to which reference may be had for adisclosure calculating machine, including mechanism not specificallydisclosed herein. The present application is a division of the copendingAvery application Serial Number 228,613, filed September 6, 1938, nowPatent No. 2,376,954, granted May 29, 1945, the latter disclosing andclaiming certain automatic shift arresting mechanism illustrated in theaccompanying drawings, which application, now Patent No. 2,376,954, isin turn, a continuation of the application on which the aforementionedPatent No. 2,211,736 was issued.

In a machine of the general type disclosed in the aforesaid Avery PatentNumber 2,211,786, a power transmission mechanism is provided Serial No.554,557

whereby the shiftable carriage may be moved laterally by power derivedfrom the motor. This motor may operate continuously, but preferably iscontrolled by an electric switch, automatically closed upon operation ofthe carriage shift controls, as also disclosed in detail in theaforesaid Avery Patent Number 2,211,736. Carriage shifting is effectedby such power transmission mechanism controlled by a key, or preferably,two keys whereby the mechanism may be rendered effective to cause thecarriage to be shifted in one, or selectively, in the other direction.

When a carriage shift control key is depressed by the operator of such amachine, and carriage is moved in the selected direction, into thedesired operating position. The power transmission functioning in thisoperation should operate cyclically so that, even though the shiftcontrol key is released after the power transmission has commenced butbefore it has completed a cycle, the carriage will be power driven intothe next operating position.

The manner in which the above and other objects of the invention areaccomplished will be readily understood on reference to the followingspecification when read in conjunction with the accompanying drawingswherein:

Figure 1 is a plan View of a Marchant calculating machine embodying thepresent invention;

Figure 2 is a side View illustrating the'carriage shifting powertransmission'inechanism and con trols therefor Fig. 2A is a detail viewshowing a portion of Fig. 2;

Figure 3 is a detail sectional view showing the mechanism which effectscyclic disengagement of the power transmission mechanism; and

Fig. t is a sectional view through the power transmission mechanism,illustrating its connection to the carriage, and is taken along the line4-4 of Figure 2.

Shift actuating mechanism .The machine is provided with a motor (notshown) which constitutes the driving means for the carriage shift powertransmission mechanism I309 (Figure 2). The power is transmitted fromthe motor through suitable gears and shafts to gear 362 (Figure 4) todrive this power transmission mechanism. Said gear is rotatably mountedon shaft |308which is positioned between the center and right sideframes 500 and 5M, respectively, of the machine. Gear 648, which is usedto drive unrelated mechanisms (not shown), is also rotatably mounted onshaft I300 by a flanged sleeve I301. which is keyed to by three the hubofgear 302 and secured by rivets to gear 048, the same rivets affixing adished ring gear supporting disc I300 to the said gear 008.

The power in Figures 2 and 4, comprises an internal ring gear I3l0secured to the supporting disc I303 and enmeshed with three planetarygears I3 I 6 riveted to each of three shafts "II, respectively. whichextend through clearance holes provided in a ratchet wheel I303, andhave end bearings in plates I3l8 and I3I9. These plates and the ratchetwheel are secured together asa rigid unit studs I303a. The gears I3I3also mesh with a sun gear I320 formed upon one end of a sleeve I32! tothe opposite end of which a second ratchet wheel I305 is keyed. SleeveI32I and wheel I305 are journaled on the shaft I303.

Gear teeth I322 formed on the shafts I3II mesh with a second sun gearI321 journaled on sleeve I32I. Secured to gear I32! is a gear I32d bywhich power is transmitted from this mechanism to a cyclically operatedshift drive train.

This power transmission mechanism may beselectively controlled so as todrive the shift drive train in either direction by means comprising aselectively settable control member I300. Gear 332 is always rotated inthe same direction when the motor is running, driving gear 648 and ringgear I3I5 so that planetary gears I3I6, and their associated gears I322will normally revolve idly about sun gear I321. If the ratchet wheelI303 is held, however, as when dog I302 (Figure 2) of control memberI300 is rocked into holding engagement therewith, revolution of theplanetary gears I3I5, I322 about sun gears I320 and I321 is preventedand said transmission mechanism, as shown planetary gears function asidlers to transmit the drive to the sun gear I321, and its associatedgear I324. If, however, the other ratchet wheel I303 is held by dog I304(Figure 2) of control member I303, being rocked into holding engagementtherewith, sun gear I320 will beheld'fstationary and the planetary gearsI3I3I322 will all rotate about their own centers and also revolve aboutsun gear I320, thereby driving the gear I324 in the opposite direction.This selective reversal of rotation of gear I320 is utilized to drivethe carriage shift train selectively in one or the other direction.

Power is transmitted from gear I320 to this drive train by meanscomprising a gear I326 meshing with gear I320, gear I320 being rotatablymounted on the, shaft I33I (Figure 4) between friction discs I330 andI332 keyed to said shaft. A sleeve I333 is also mounted on shaft I33I,and a spring I33? is compressed between a washer I338, located injuxtaposition with the sleeve I and lock nuts I330 on the threaded endof shaft I33I. This construction provides for a frictional driveconnection between gear I320 and shaft I33I effected by the keyed discsI330 and I332, which are pressed against the gear I323 by spring I33?bearing against the washer I338, the sleeve I333, and an interposed discI335, the purpose of which will be explained hereinafter.

The shaft I33I is supported in a suitable bearing I380 securely mountedin a frame of the machine, and a sleeve bearing I330 riveted to an anglebracket I303. A bevel gear IB II is fixed on the end of the shaft I33Iand meshes with a bevel gear I302 securely mounted on the lower end ofvertical shaft 333, also supported in the angle bracketI3 I3 secured tothe base plate 205i of the machine.

The aforesaid shaft 330 is supported at its upper end by bracket 355secured to'the back frame plate of the machine. The upper end of shaft330 also has fixed thereto a hub and plate assembly 333 on which aremounted two diametrically disposed rollers 332 adapted to engage betweenthe teeth of rack 330, mounted on the shiftable car- I riage 250 (seealso Figure 1) and thereby, upon rotation of the shaft 330 by the powertransmission mechanism serves to drive the carriage laterally to theright or to the left, selectively.

It should be noted that the several teeth of the rack 330 are spacedapart'from each other a distance equal to the spacing between each ofthe different carriage positions. Thus, each half rotationof the shafts330 and I33I will shift the carriage from one position to constitute onecycle of operation of the shift mechanism.

Shift control mechanism The controls for causing the power transmis- Thekeys I005 and I006 comprise vertically sliding stems, which areconnected by means of links I00? and M03 (Figure 2) with a common pinI300 pivotally attached thereto, while a spring I000, tensioned betweenone of said links and a stud on the machine frame, normally urges bothof the keys I505 and I003 upwardly. Upon depression of the key I005, thepin I003 is moved to the right, and upon depression of the key I000 thepin I000 is moved to the left, as viewed in Figure 2. A stationarymember I II'I guides the pin I309 in either its right or left handmovement and also serves as an interlock so that neither one of the keysI005 or I003 can be depressed when the other one is in a depressedposition.

Either right or left hand movement of the pin I300 will be transmittedthrough bifurcated arm I082 to rock the shaft I005, to which arm I002 1is pinned, clockwise or counter-clockwise, de-

pending upon which of the keys is depressed. Disposed on the shaft I085,adjacent to each other, are two similar V-shaped members I000 and I I8I,each of which is provided with two facing lugs I000. A spring I090 iscompressed between these four lugs so that a rocking movement in eitherdirection can be transmitted from one of the V-shaped members to theother through the spring M30. Member I580 is pinned to the shaft M andis rocked by the movement of arm I032, thus rocking the member IIIOIwhich is free on the shaft I035, and which has a downwardly extendingarm pivotally connected to the link I433 which is thus moved to theright lever I313 which is provided with a lateral projection Mil,normally engaging in a notch I414 the next, and will provided wherebythe dein the rearward end of link I433 heldin engagement with saidprojection by spring I350 tensionedlietween link I433 and the machineframe.

The rocking of lever I315 imparts longitudinal movement to a link I314pivoted to the upper end thereof and provided at its rear end with anaperture II2 in which are two facing lugs I5I0a and I5I0b. Juxtaposedthe rear end of link I314 is a link III I (Fig. 2A) with an identicalaperture, I5I2a, also with two facing lugs I5I0c and I5I0d. Link I314and link II are yieldingly connected by compression spring I 5I2 locatedover the four lugs, and link I5 is pivotally connected at its forwardend to the control member I300 by a stud I5I3, so that longitudinalmovement of link I314 will cause rocking movement of the control memberI308 about the fixed support shaft I "I. The control member I 303 has arearwardly extending arm provided with a dog I302 adapted to engageratchet wheel I303, and a downwardly extending arm provided with a dogI304 adapted to engage the ratchet wheel I305.

Thus, upon depression of key I406 to initiate a carriage shift to theleft, the link I483 is moved to the right, as viewed in Figurev 2,imparting counter-clockwise movement to the lever I315, leftwardmovement to link I314, and counterclockwise movement to the control dogI308, moving dog I304 into holding engagement with the ratchet wheelI305 to cause transmission of the drive to the carriage, as has beenpreviously described.

When a right hand carriage shift is desired, the key I405 is depressed,thus moving the link I483 to the left to rock lever I315 in a clockwisedirection. This rocking movement of lever I315 moves the link I314 tothe right causing the dog I302 to engage the ratchet I303, thusreversing the direction of rotation of the carriage shifting mechanism.

According to the present invention means are provided whereby either ofthe dogs I302 or I304 is held in engagement with its respective ratchetwheel during approximately the first threequarters of the shift cycle,to prevent interruption of the driving connection during any initiatedshift cycle, no matter how quickly the respective shift key is released.On a leftward extension of the control member I308 (Figure 2) is aformed ear I354 (see also Figure3), adapted to engage a projection I353of a latch I350, pivotally mounted at I35I and urged into engagementwith said ear by a spring I352 which is tensioned between the latch anda centralizer I364. When control member I308 is moved either clockwiseor counter-clockwise, the ear I354 is released from against the face oflug I 353 on latch I350 and the latch then rocks about shaft I 3.5Iunder the tension of spring I352 and seats its projection I353 eitherabove or below ear I354, thus latching the control member I 300 againstreturn movement.

Provision is made whereby additional tension is put on spring I352 atthe beginning of the cycle of operation of the power transmissionmechanism so as to insure seating of the projection I353 under or overthe ear I354. For this purpose, the centralizer I364, which is pivotedon a frame pin I365, has the upper end of spring I352 attached to theextreme left end thereof. When the shaft I33I first begins to rotate,rollers I363 which are mounted on the disc I330 revolve, and in theirmovement cam the centralizer I364 upwardly, thereby exerting more duringthe latter 6 and more tension on the spring I352 until the shaft I33Ihas made one-quarter of a rotation.

Provision is made for releasing the ear I354 from latch I350 at apredetermined point in the cycle regardless of in which direction thecarriage shift drive train is rotating. For this purpose a cam I334mounted on the sleeve I333 includes two opposite rises over which a noseI351 of the latch I350 rides. the two rises being required because, aspreviously explained, one-half rotation of shaft I33I is a full cycle ofoperation of the shift mechanism. The cam I334 is free on the sleeveI333 and is driven by a lost motion connection with shaft I33Icomprising the disc I335 which is keyed to shaft I33I and provided withtwo shoulders I330 on opposite sides thereof. Upon clockwise rotation ofthe disc I 335 from the position shown in Figure 3, a pin I36I on thecam I334 is engaged by the rightmost shoulder I360 and the nose I351 iscammed upwardly part of the cycle. Upon counter-clockwise rotation ofthe disc I335 from the position shown in Figure 3, the leftmost shoulderI360 engages the stud I35I of cam I334 and drives the latter in acounterclockwise direction. During the latter part of the cycle, therise of cam I334 opposite the stud I36I engages the nose I351 and camsthe latch I350 counter-clockwise to releasing position.

When the latch I350 is thus released, the control member I308 isautomatically centralized to remove the effective dog I302 or I304 fromengagement with its ratchet wheel. For this purpose a lever I4I0 whichis pivotally mounted in the machine frame at I4 is provided with a lugI4I2 extending laterally into engagement with lever I315 above the pivotI316, and an adjustable lug I4I5 having an offset I 4.I'8 engaging thelever I 315 below said pivot, and pressed against the lever I315 by aspring I400 tensioned between the free end of lever I0 and a pin H onthe machine frame. Thus the centralizer I4I0 tends to maintain the leverI315 in a central position in which the control member I308 will beineffective, and will return it to said central position automaticallyupon release of latch I350, provided the operating keys I405 and I405 orother shift controlling means (not shown) are released.

Although the drive to the carriage through the power transmissionmechanism is thus terminated at approximately three-quarter cycleposition, the shift drive train will be rotated through the remainder ofits cycle, consisting of one-quarter of a revolution of shaft I33I, bythe centralizer I364, pressed by spring I352 against rollers I363 ondisc I330 secured to said shaft.

It will be noted that the load imposed upon the carriage shiftingmechanism by the frictional resistance set up in shifting the carriageand in rotating the shafts 334 and I33I etc., is also applied throughthe planetary gearing to whichever ratchet wheel I303 and I305 isengaged by its respective one of the dogs I302, I304, the ratchet wheelexerting this force against its respective dog. This load may be of sucha magnitude as to tend to prevent a spring such as I 400 from returningthe member I308 to its illustrated neutral position after the carriageis shifted to a desired operating position. The centralizer I364 acts toremove part of this load upon the engaged ratchet wheel during thelatter part of each shift cycle by aiding the transmission mechanism indriving the carriage ahead during this period. Therefore, any tendencyof the engaged ratchet wheel to hold the member I306 from assesses beingreturned is reduced during the latter part Although the invention hasbeen illustrated as I embodied in a calculating machine, andparticularly in the carriage shifting mechanism there-.

of, it will be understood that the invention is not restricted to suchparticular uses, but is generally applicable to any kind of machine inwhich a cyclically operating power transmisison mechanism is to beemployed.

What I claim is:

1. In a cyclically operable power transmission for releasably connectingarotatable driving element with a cyclically operable rotatable drivenelement; the combination with means for selectively effecting a drivingconnection between said driving and driven elements comprising a controlmember selectively adjustable to an active position to cause saiddriving element to rotate said driven element, and to an inactiveposition to permit rotation of said driving element without transmissionof driving movement to said driven element; of means for latching saidcontrol member in active position, a device responsive to movement ofsaid member to active position and operable independently of said drivenelement for controlling movement of said latching means to latchingposition, means operating in timed relationship with said driven elementfor releasing said control member from said latching means at a point ineach cycle of operation of said driven element which is antecedent tothe arrival of said driven element at its full cycle position, and meansfor returning said control member to said inactive position upon releasethereof from said latching means.

2. In a cyclically operable power transmission for releasably connectinga rotatable driving element with a cyclically operable rotatable drivenelement; the combination with means for selectively effecting a drivingconnection between said driving and driven elements comprising a controlmember selectively adjustable to an active position to cause saiddriving element to rotate said driven element, and to an inactiveposition to lid out transmission of driving movement to said drivenelement; oi means for latching said con trol member in active positionupon movement or said member thereto comprising a rockable latch memberand means actuated by said driven element and including a normallytensioned spring for rocking said latch member into latchingrelationship with respect to said control member, means operating intimed relationship with said driven element for releasing said controlmember from said 'latchingmeans at a point in each cycle of operation ofsaid driven element which is antecedent to the arrival oi said drivenelement at its full cycle position, and means for returning said controlmember to said inactive position upon release thereof from said latchingmeans.

i. In a cyclically operable power transmission for releasably connectinga rotatable driving element with a cyclically operable rotatable drivenelement; the combination with means for selectively efiecting a drivingconnection between said driving and driven elements comprising a controlpermit rotation of said driving element without transmission of drivingmovement to said driven element; of means for latching said controlmember in active position upon movement of said member theretocomprising a rockable latch member and means actuated by said drivenelement for rocking said latch member into latch= ing relationshipwithrespect to said control member, means operating in timedrelationship with said driven element for releasing said control memberfrom said latching means at a point-in each cycle of operation of saiddriven element which is antecedent to the arrival of said driven elementat its full cycle position, and means for returning said control memberto said inactive position upon release thereof from said latching means.

3. In a cyclically operable power transmission for releasably connectinga rotatable driving element with a cyclically operable rotatable drivenelement; the combination with means for selectively effecting a drivingconnection between said driving and driven elements comprising a controlmember selectively adjustable to an active position to cause saiddriving element to rotate said driven element, and to an inactiveposition to permit rotation of said driving element withmemberselectively adjustable to an active position to cause said drivingelement to rotate said driven element, and to an inactive position topermit rotation of said driving element without transmission 01" drivingmovement to said driven element; of means for latching said controlmember in active position, a device responsive to movement of saidmember to active position and operable independently of said drivenelement for controlling movement of said latching means to latchingposition, means operating in timed relationship with said driven elementfor releasing said. control member from said latching means at a pointin each cycle of operation of said driven element which is antecedent tothe arrival of said driven element at its full cycle position, means forreturning said control member to said-inactive position upon releasethereof from said latching means, and means for advancing said drivenelement to full cycle position and bringing it to rest therein uponcessation oi the transmission of driving movement from said drivingelement to said driven element.

5. In a cyclically operable, reversible power transmission forreleasably connecting a rotatable driving element. with a cyclicallyoperable rotatable driven element; the combination with means forselectively effecting a driving connection between said driving anddriven elements comprising a control member selectively adjustable to afirst active position to cause said driving element to rotate saiddriven element in one direction; to a second active position to causesaid driving element to rotate said driven element in the oppositedirection; and to a third inactive position to permit rotation of saiddriving element without transmission of driving movement to said drivenmember; of means for latching said control member in the one or theother active position upon movement of said member to either of saidpositions, means operating in timed relationship with said drivenelementior releasing said control member from said latching means at-apoint in each cycle of operation of said driven element which issubstantially the same during rotation of said driven element in eitherdirection and which is antecedent to the arrival or said driven elementat its full cycle position, means for returning said-control memher tosaid inactive position upon release thereof from said latching means,and means for advancing said driven element to full cycle position andtransmission oi. driving movement from said driving element to saiddriven element.

6. In a cyclically operable, reversible power transmission. forreleasably connecting a rotatable driving element with a cyclicallyoperable rotatable driven element; the combination with means forselectively effecting a driving connection between said driving anddrivenelements comprising a control member selectively adjustable to afirst active position to cause said driving element to rotate saiddriven element in one direction; to a secondactive position to causesaid driving element to rotate said driven element in the oppositedirection; and to a third inactive position to permit rotation of saiddriving element without transmission of driving movement to said drivenmember; or means for latching said control member in the one or theother active position upon movement of said member to either of saidpositions, means operating in timed relationship with said drivenelement for releasing said control member from said latching means at apoint in each cycle of operation of said driven element which issubstantially the same during rotation of said driven element in eitherdirection and which is antecedent to the arrival of said driven elementat its full cycle position; said releasing means comprising a latchreleasing cam and a lost-motion actuator for said cam driven by saiddriven element, means for returning said control member tosaid inactiveposition upon release thereof from said latching means, and means foradvancing said driven element to full cycle position and bringing it torest therein upon cessation of the transmission of driving movement fromsaid driving element to said driven element. V

7. In a cyclically operable, reversible power transmission forreleasably connecting a rotatable driving element with a cyclicallyoperable rotatable driven element; the combination with means forselectively efiecting a driving connection between said driving anddriven elements comprising a control member selectively adjustable to afirst active position to cause said driving element to rotate saiddriven element in one direction; to a second active position to causesaid driving element to rotate said driven element in the oppositedirection; and to a third inactive position to permit rotation oi! saiddriving element without transmission of driving movement to said drivenmember; of means for latching said control member in the one or theother active position upon movement of said member to either of saidpositions comprising a rockable latch member and means actuated by saiddriven element for rocking said latch member into latching relationshipwith respect to said control member, means operating in timedrelationship with said driven element for releasing said control memberfrom said latching means at a point in each cycle of operation or saiddriven element which is substantially the same during rotation of saiddriven element in either direction and which is antecedent to thearrival of said driven element at its full cycle position,

, means for returning said control member to said inactive position uponrelease thereof from said latching means, and means for advancing saiddriven element to full cycle position and bringing it to rest thereinupon cessation of the trans mission of driving movement from saiddriving element to said driven element.

8. In a cyclically operable, reversible power 10: transmission forreleasably connecting a rotatable driving element with a cyclicallyoperable rotatable driven element; the combination with means forselectively eflecting a driving connec-. tion between said driving anddriven elements comprising a control members'electively adjustable to afirst active position to cause said driving element to rotate saiddriven element in one direction; to a second active position to causesaid driving element to rotate said driven element in the oppositedirection: and to a third inactive position to permit rotation of saiddriving element without transmission of driving movement to said drivenmember; of means for latching said control member in the one or theother active position upon movement oi said member to either of saidpositions comprising a rockable latch member and means actuated by saiddriven element for rocking said latch member into latching relationshipwith respect to said control member, means operating in timedrelationship with said driven element for releasing said control memberfrom said'latching means at a point in each cycle of operation of saiddriven element which is substantially the same during rotation 01 saiddriven element in either direction and which is antecedent to thearrival of said driven element at its full cycle position; saidreleasing means comprising a latch releasing cam and a lost-motionactuator for said cam driven by said driven element, means for returningsaid control member to said inactive position upon release thereof fromsaid latching means, and means for advancing said driven element to fullcycle position and bringing it to rest therein upon cessation of thetransmission of driving movement from said driving element to saiddriven element.

9. In a cyclically operable, reversible power transmission forreleasably connecting a rotatable driving element with a cyclicallyoperable rotatable driven element; the combination with means forselectively effecting a driving connection between said driving anddriven elements comprising a control member selectively adjust able to afirst active position to cause said driving element to rotate saiddriven element in one direction; to a second active position to causesaid driving element to rotate said driven element in the oppositedirection; and to a third inactive position to permit rotation of saiddriving element without transmission of driving movement to said drivenmember; of means for latching said control member in the one or theother active position upon movement of said member to either of saidpositions comprising a rockable latch for-rocking said latch member intolatching re lationship with respect to said control member;

means operating in timed relationship with said driven element forreleasing said control member from said latching means at a point ineach cycle of operation of said driven element which is substantiallythe same during rotation of said driven element in either direction andwhich is antecedent to the arrival of said driven element at its fullcycle position, means for returning said control member to said inactiveposition upon release thereof from said latching means, and means foradvancing said driven element to full cycle position and bringing it torest therein upon cessation of the transmission of driving movement fromsaid driving element to said driven element.

aesasss 10. In a cyclically operable, reversible power transmission forreleasably connecting a rotata- 'ble driving element with a cyclicallyoperable rotatable driven element; the combination with means forselectively efiecting a driving connection between said driving anddriven elements comprising a control member selectively adjustable to afirst active position to cause said driving element to rotate saiddriven element in one direction; to a second active position to causesaid driving element to rotate said driven element in the oppositedirection; and to a third inactive position to permit rotation of saiddriving element without transmission of driving movement to said drivenmember; of means for latching said control member in the one or theother active position upon movement of said member to either of saidpositions comprising a rockable latch member and means actuatedby saiddriven element and including a normally tensioned spring for rockingsaid latch member into latching relationship with respect to saidcontrol member, means operating in timed relationship with said drivenelement for releasing said control member from said latching means at apoint in each cycle of operation of said driven element which issubstantially the same during rotation of said driven element in eitherdirection and which is antecedent to the arrival of said driven elementat its full cycle position; said releasing means comprising a latchreleasing cam and a lost-motion actuator for said cam driven by saiddriven element, means for returning said con- .trol member to saidinactive position upon release thereof from said latching means, andmeans for advancing said driven element to full cycle position andbringing it to rest therein upon cessation of the transmission ofdriving movement from said driving element to said driven element.

11. In a cyclically operable power transmission for releasablyconnecting a rotatable driving element with a cyclically operablerotatable driven element; the combination with means for selectivelyefiecting a driving connection between said driving and driven elementscomprising a device rotatable by said driving element and a controlmember selectively adjustable to an active position to restrain saiddevice against rotation by said driving element and thus cause saiddriving element to rotate said driven element, and to an inactiveposition to permit rotation of said device by said driving elementwithout transmission of driving movement to said driven element; theaction of said driving element upon said device when said device isrestrained by said control member tending to retain said control memberin said active position; of means for latching said control member inactive position upon movement of said member thereto, means operating intimed relationship with said driven element for releasing said controlmember from said latching means at a point in each cycle of operation ofsaid driven element which is antecedent to the arrival of said drivenelement at its full cycle position, spring means tending to return saidcontrol member to said inactive position upon release thereof from saidlatching means, and means for advancing said driven element to fullcycle position and effective to minify the aforesaid action of saiddriving element upon said device to a sufilcient extent to permit saidspring means to return said control member to said inactive position;said advancing means being also effective to bring said driven elementto rest .1

. driving l2 full cycle position upon cessation of the transmission ofdriving movement from said driving element to said driven element.

12. In a cyclically operable power transmission for releasablyconnecting a rotatable driving element with a cyclically operablerotatable driven element; the combination with means for selectivelyeffecting a driving connection between said driving and driven elementscomprising two devices rotatable by said driving element and a controlmember selectively adjustable to a first active position to restrain oneof said devices against rotation by said driving element and thus causesaid driving element to rotate said driven element in one direction; toa second active position to restrain the other of said devices againstrotation by said driving element and thus cause said driving element torotate said driven element in the opposite direction; and to a thirdinactive to permit rotation of both of said devices by said drivingelement without transmission of driving movement to said driven element;the action of said driving element upon said devices when either of saiddevices is restrained by said control member tending to retain saidcontrol mem-' ber in its instant active position; of means for latchingsaid control member in the one or the other active position uponmovement of said member to either of said positions, means operating intimed relationship with said driven element for releasing said controlmember from said latching means at a point in each cycle of operation ofsaid driven element which is substantially the same during rotation ofsaid driven element in either direction and which is antecedent to thearrival of said driven element at its full cycle position, spring meanstending to return said control member to said inactive position uponrelease thereof from said latching means, and means for advancing saiddriven element to full cycle position and effective to minify theaforesaid action of said driving element upon said device to-a suficientextent to permit said spring means to return said control member to saidinactive position; said advancing means being also effective to bringsaid driven element to rest in full cycle position upon cessation of thetransmission of driving movement from said driving element to saiddriven element.

13. In a cyclically operable power transmission for releasablyconnecting a rotatable driving element with a cyclically operablerotatable driven element; the combination with means for selectivelyefiecting a driving connection between said driving and driven elementscomprising two devices rotatable by said driving element and a controlmember selectively adjustable to a first active position to restrain oneof said devices against rotation by said driving element and thus causesaid driving element in one direction; to a second active position torestrain the other of said devices against rotation by said drivingelement and thus cause said driving element to rotate said drivenelement in the opposite direction; and to a third inactive to permitrotation of both of said devices by said element without transmission ofdriving movement to said driven element; the action of said drivingelement upon said devices when either of said devices is restrained bysaid control member tending to retain said control member in its instantactive position; of means for latching said controlmember in the one orthe other active position upon movement of said member to either of saidpositions, means opelement to rotate said driven crating in timedrelationship with said driven element for releasing said control memberfrom said latching means at a point in each cycle of operation of saiddriven element which is substantially the same during rotation of saiddriven element in either direction and which is antecedent to thearrival of said driven element at its full cycle position; saidreleasing means comprising a latch releasing cam and a lost-motionactuator for said cam driven by said driven element. spring meanstending to return said control member to said inactive position uponrelease thereof from said latching means, and means for advancing saiddriven element to full cycle position and effective to minify theaforesaid action of said device to a suflicient extent to permit saidspring means to return said control member to said inactive position;said advancing means being also effective to bring said driven elementto rest in full cycle position upon cessation of the transmission ofdriving movement from said driving element to said driven element.

14. In a calculating machine having a motor and devices cyclically andreversibly operable thereby; the combination with a forward driving andreversing power transmission mechadriving element upon said 14 nism forconnecting said motor to said devices and controls selectively settableto cause said mechanism to eifect a driving connection between saidmotor and said devices and transmit continuous rotational movement ineither direction to said devices, or to interrupt said drivingconnection; of means for preventing interruption of said drivingconnection except at a predetermined cyclic position of said devices,comprising means for retaining said controls in set positions, and meansactuated by said devices and including a lost-motion connection betweensaid devices and said retaining means, for releasing said controls fromsaid retaining means when said devices reach substantially the samecyclic position during rotation in either direction.

HAROLD T. AVERY.

REFERENCES CITED The following references areof record in the file ofthis patent:

UNITED STATES PATENTS

